Per Vognsen

@pervognsen
2.5K Followers
356 Following
10K Posts
I like programming and understanding how stuff works. My background is in systems programming and game development.
We've released a demo of the project @CanLehmann and I have been working on: @verijit is a meta-tracing Verilog emulator that specializes the simulated core to the machine code that is being executed on top of it. Was lots of fun to work on! I'm quite happy with the results too, we reach two orders of magnitude improvement over Verilator for a simple RISC-V core
https://www.youtube.com/watch?v=PXgUsEjvAOY
Verijit – Up to 100x faster Verilog simulation

YouTube

For my game's terrain, I've long mulled over how to combine the epicness of grand mountains with the "what's around the corner?" intrigue of smaller cliffs and hills.

On top of that, how to meaningfully integrate my erosion technique into it.

After a lot of fiddling over the past two days, I think I may be onto something.
#GameDev #ProcGen

The Trusted Computing Base of the CompCert Verified Compiler, https://arxiv.org/abs/2201.10280
The Trusted Computing Base of the CompCert Verified Compiler

CompCert is the first realistic formally verified compiler: it provides a machine-checked mathematical proof that the code it generates matches the source code. Yet, there could be loopholes in this approach. We comprehensively analyze aspects of CompCert where errors could lead to incorrect code being generated. Possible issues range from the modeling of the source and the target languages to some techniques used to call external algorithms from within the compiler.

arXiv.org

Multiple parties have come together to create a new fairly complete #DOS port of #SDL3 (via #DJGPP)

#MSDOS #VESA #RetroComputing #RetroGaming #SDL

https://github.com/libsdl-org/SDL/pull/15377

Add DOS platform support (DJGPP) by AJenbo · Pull Request #15377 · libsdl-org/SDL

This is the combined work of @icculus @madebr @glebm @jayschwa @ccawley2011 and me rounding it off with stability fixes and missing features, thanks to everyone for pitching in. This is a fairly c...

GitHub

The SDL organization has an official position on LLMs and generative AI now: don't use it.

https://github.com/libsdl-org/SDL/issues/15350

LLM Policy? · Issue #15350 · libsdl-org/SDL

I've noticed the use of Copilot within a few reviews (13277 and 12730) which concerns me given the vast amount of issues associated with this technology (ethical, environmental, copyright, health, ...

GitHub
No one can force me to have a secure website!!!

YouTube
The NBA Jam repo on historicalsource has a bunch of doc files that are a time capsule from 1992. Here's a fun excerpt, relative to what actually happened: "The NBA has been cautious about entering the European market, it's understandable. The NBA, it is believed, will grant franchises and expand into Europe within the next few years." https://github.com/search?q=repo%3Ahistoricalsource%2Fnbajam-complete%20doc&type=code

Here are the slides for my "Live++: A Bag of Tricks" talk presented at Guerrilla Games last Friday.
Enjoy!

PPTX:
https://liveplusplus.tech/downloads/Guerrilla_Games_2026_Live++_A_Bag_of_Tricks.pptx

PDF:
https://liveplusplus.tech/downloads/Guerrilla_Games_2026_Live++_A_Bag_of_Tricks.pdf

#cpp

22 years later, I made a "remaster" of our old demo Syntonic Dentiforms. Now on Windows, Linux, Mac and Web, with cleaned up source code and ported from ancient closed source libraries (D3DX, etc.) to sokol_gfx, sokol_audio, stb_vorbis (they are nice!). Here's a blog post: https://aras-p.info/blog/2026/04/13/Syntonic-Dentiforms-redux/  #demoscene
Syntonic Dentiforms redux · Aras' website

Aras' website

INTRODUCTION TO SPHERICAL HARMONICS FOR GRAPHICS PROGRAMMERS

finally done

https://gpfault.net/posts/sph.html

Introduction to Spherical Harmonics for Graphics Programmers